git.sesse.net Git - vlc/blob - include/modules_inner.h

   1 /*****************************************************************************
   2  * modules_inner.h : Macros used from within a module.
   3  *****************************************************************************
   4  * Copyright (C) 2001 VideoLAN
   5  * $Id: modules_inner.h,v 1.16 2002/04/24 00:36:24 sam Exp $
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Check that we are within a module.
  26  *****************************************************************************/
  27 #if !( defined( MODULE_NAME ) || defined( MAKE_DEP ) )
  28 #  error "You must define MODULE_NAME before using modules_inner.h !"
  29 #endif
  30
  31 /*****************************************************************************
  32  * Add a few defines. You do not want to read this section. Really.
  33  *****************************************************************************/
  34
  35 /* Explanation:
  36  *
  37  * if user has #defined MODULE_NAME foo, then we will need:
  38  * #define MODULE_STRING "foo"
  39  * #define MODULE_VAR(blah) "VLC_MODULE_foo_blah"
  40  *
  41  * and, if __BUILTIN__ is set, we will also need:
  42  * #define MODULE_FUNC( zog ) module_foo_zog
  43  *
  44  * this can't easily be done with the C preprocessor, thus a few ugly hacks.
  45  */
  46
  47 /* I can't believe I need to do this to change « foo » to « "foo" » */
  48 #define STRINGIFY( z )   UGLY_KLUDGE( z )
  49 #define UGLY_KLUDGE( z ) #z
  50 /* And I need to do _this_ to change « foo bar » to « module_foo_bar » ! */
  51 #define CONCATENATE( y, z ) CRUDE_HACK( y, z )
  52 #define CRUDE_HACK( y, z )  y##__MODULE_##z
  53
  54 #define MODULE_VAR( z ) "VLC_MODULE_" #z
  55
  56 /* If the module is built-in, then we need to define foo_InitModule instead
  57  * of InitModule. Same for Activate- and DeactivateModule. */
  58 #ifdef __BUILTIN__
  59 #   define _M( function )          CONCATENATE( function, MODULE_NAME )
  60 #   define __VLC_SYMBOL( symbol )  CONCATENATE( symbol, MODULE_NAME )
  61 #   define DECLARE_SYMBOLS         ;
  62 #   define STORE_SYMBOLS           ;
  63 #else
  64 #   define _M( function )          function
  65 #   define __VLC_SYMBOL( symbol  ) CONCATENATE( symbol, MODULE_SYMBOL )
  66 #   define DECLARE_SYMBOLS         module_symbols_t* p_symbols;
  67 #   define STORE_SYMBOLS           p_symbols = p_module->p_symbols;
  68 #endif
  69
  70 #define MODULE_STRING STRINGIFY( MODULE_NAME )
  71
  72 /*
  73  * InitModule: this function is called once and only once, when the module
  74  * is looked at for the first time. We get the useful data from it, for
  75  * instance the module name, its shortcuts, its capabilities... we also create
  76  * a copy of its config because the module can be unloaded at any time.
  77  */
  78 #define MODULE_INIT_START                                                     \
  79     DECLARE_SYMBOLS;                                                          \
  80     int __VLC_SYMBOL( InitModule ) ( module_t *p_module )                     \
  81     {                                                                         \
  82         int i_shortcut = 0;                                                   \
  83         struct module_config_s* p_item;                                       \
  84         p_module->psz_name = MODULE_STRING;                                   \
  85         p_module->psz_longname = MODULE_STRING;                               \
  86         p_module->psz_program = NULL;                                         \
  87         p_module->i_capabilities = 0;                                         \
  88         p_module->i_cpu_capabilities = 0;
  89
  90 #define MODULE_INIT_STOP                                                      \
  91         STORE_SYMBOLS;                                                        \
  92         p_module->pp_shortcuts[ i_shortcut ] = NULL;                          \
  93         p_module->i_config_items = 0;                                         \
  94         for( p_item = p_config;                                               \
  95              p_item->i_type != MODULE_CONFIG_HINT_END;                        \
  96              p_item++ )                                                       \
  97         {                                                                     \
  98             if( p_item->i_type & MODULE_CONFIG_ITEM )                         \
  99                 p_module->i_config_items++;                                   \
 100         }                                                                     \
 101         vlc_mutex_init( &p_module->config_lock );                             \
 102         p_module->p_config = config_Duplicate( p_config );                    \
 103         if( p_module->p_config == NULL )                                      \
 104         {                                                                     \
 105             intf_ErrMsg( MODULE_STRING                                        \
 106                          " InitModule error: can't duplicate p_config" );     \
 107             return( -1 );                                                     \
 108         }                                                                     \
 109         for( p_item = p_module->p_config;                                     \
 110              p_item->i_type != MODULE_CONFIG_HINT_END;                        \
 111              p_item++ )                                                       \
 112         {                                                                     \
 113             p_item->p_lock = &p_module->config_lock;                          \
 114         }                                                                     \
 115         return( 0 );                                                          \
 116     }
 117
 118 #define ADD_CAPABILITY( cap, score )                                          \
 119     p_module->i_capabilities |= 1 << MODULE_CAPABILITY_##cap;                 \
 120     p_module->pi_score[ MODULE_CAPABILITY_##cap ] = score;
 121
 122 #define ADD_REQUIREMENT( cap )                                                \
 123     p_module->i_cpu_capabilities |= CPU_CAPABILITY_##cap;
 124
 125 #define ADD_PROGRAM( program )                                                \
 126     p_module->psz_program = program;
 127
 128 #define ADD_SHORTCUT( shortcut )                                              \
 129     p_module->pp_shortcuts[ i_shortcut ] = shortcut;                          \
 130     i_shortcut++;
 131
 132 #define SET_DESCRIPTION( desc )                                               \
 133     p_module->psz_longname = desc;
 134
 135 /*
 136  * ActivateModule: this function is called before functions can be accessed,
 137  * we do allocation tasks here, and maybe additional stuff such as large
 138  * table allocation. Once ActivateModule is called we are almost sure the
 139  * module will be used.
 140  */
 141 #define MODULE_ACTIVATE_START                                                 \
 142     int __VLC_SYMBOL( ActivateModule ) ( module_t *p_module )                 \
 143     {                                                                         \
 144         p_module->p_functions =                                               \
 145           ( module_functions_t * )malloc( sizeof( module_functions_t ) );     \
 146         if( p_module->p_functions == NULL )                                   \
 147         {                                                                     \
 148             return( -1 );                                                     \
 149         }                                                                     \
 150         STORE_SYMBOLS;
 151
 152 #define MODULE_ACTIVATE_STOP                                                  \
 153         return( 0 );                                                          \
 154     }
 155
 156 /*
 157  * DeactivateModule: this function is called after we are finished with the
 158  * module. Everything that has been done in ActivateModule needs to be undone
 159  * here.
 160  */
 161 #define MODULE_DEACTIVATE_START                                               \
 162     int __VLC_SYMBOL( DeactivateModule )( module_t *p_module )                \
 163     {                                                                         \
 164         free( p_module->p_functions );
 165
 166 #define MODULE_DEACTIVATE_STOP                                                \
 167         return( 0 );                                                          \
 168     }